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#include <ctype.h>
#include <stdio.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#ifndef __GNUC__
#include <io.h>
#else
#include <unistd.h>
#endif
#ifndef O_BINARY
#define O_BINARY 0
#endif
int main(int argc, char **argv) {
char *tmpbuf;
int idxfd, datfd;
long offset;
unsigned int size;
char datbuf[255];
if (argc != 3) {
fprintf(stderr, "usage: %s <datapath/datafilebasename> <index>\n", argv[0]);
exit(1);
}
tmpbuf = calloc(strlen(argv[1]) + 11,1);
sprintf(tmpbuf, "%s.idx", argv[1]);
idxfd = open(tmpbuf, O_RDONLY|O_BINARY, S_IREAD|S_IWRITE|S_IRGRP|S_IROTH);
sprintf(tmpbuf, "%s.dat", argv[1]);
datfd = open(tmpbuf, O_RDONLY|O_BINARY, S_IREAD|S_IWRITE|S_IRGRP|S_IROTH);
free(tmpbuf);
offset = atoi(argv[2]) * 6;
lseek(idxfd, offset, SEEK_SET);
read(idxfd, &offset, 4);
read(idxfd, &size, 2);
printf("offset: %ld; size: %d\n", offset, size);
lseek(datfd, offset, SEEK_SET);
read(datfd, datbuf, 40);
datbuf[40] = 0;
printf("%s\n", datbuf);
close(datfd);
close(idxfd);
return 0;
}
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